# $material-interfaces¶ To specify additional charges at material interfaces, one has to specify • material interfaces • interface state properties. See also documentation for keyword$interface-states.

$material-interfaces optional interface-number integer required apply-between-material-numbers integer_array required state-numbers integer_array required$end_material-interfaces                           optional


Explanation of specifiers

interface-number
type

integer >= 1

presence

required

An integer number to refer to interface number. Dense numbering (1, 2, …) as usual.

apply-between-material-numbers
type

integer >= 1

presence

required

Two integer numbers to refer to interface between geometry clusters, i.e. it contains the material numbers of the adjoining regions.

Is 3 4 equivalent to 4 3 in 1D? This becomes relevant for 2D and 3D simulations.

state-numbers
type

integer >= 1

presence

required

Identification numbers of interface states (e.g. fixed charge, trap or electrolyte) defined under keyword \$interface-states.

Note

There can only be one unique interface-number for the the interface between integer1 and integer2.

interface-number               = 1
apply-between-material-numbers = integer1  integer2


Here is an example which does not make sense (!):

interface-number               = 1
apply-between-material-numbers = 3 4

interface-number               = 2
apply-between-material-numbers = 3 4  ! '3 4' has already been assigned
! in 'interface-number = 1'